ENH: coordSetWriter - brought across field scaling and offsets from surface writers

Example:

    formatOptions
    {
        <writer>
        {
            // Apply offsets to field values
            fieldLevel
            {
                T   273.15; // Convert from K to C by subtracting 273.15
            }

            // Note: scale applied after application of field level
            fieldScale
            {
                p   0.001;  // Convert pressure from Pa to kPa by scaling by 0.001
            }
        }
    }